Process of desulfurizing furnace-gases.



NITED STATES ATENT OF ICE.

EMIL POLLACSEK, OF BUDAPEST, AUSTRIA-HUNGARY.

PROCESS OF DESULFURIZING FURNACE-GASES.

SPECIFICATION forming part of Letters Patent No. 709,358, datedSeptember 16, 1902.

Application filed March 10, 1902. Serial No. 97,621. (No specimens- Toall whom, it may concern.-

Be it known that I, EMIL POLLACSEK, a subject of the Emperor ofAustria-Hungary, residing at Budapest, in the Empire of Austria-Hungary,have invented certain new and useful Improvements in Processes ofDesulfurizing Furnace-Gases; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

The present invention has for its object to prevent the atmospheric airof cities and industrial centers from becoming contaminated by theadmixture of oxid of sulfur and oxid of carbon which in consequence ofthe working of furnaces hitherto in use are contained in the smoke andWaste gases emanating from the furnaces.

In order to render furnace-gases innocuous in the said respect, thepresentinvention consists in a particular way of employing lime,

which has been known as a desulfurizing agent for furnace-gases.Hitherto this agent has been utilized either by adding it to the coal inthe shape of pulverized lime or by forming disintegrated coal intobricks by the aid of lime-milk. .However, none of these methods ofapplication of lime affords the possibility of entirely freeing thefurnacegases from the oxids of sulfur.

I have succeeded in solving this important problem in a satisfactorymanner by employing lime in' such conditions which during the working ofthe furnace produce the formation of a filter for the gases ofcombustion, the said filter absorbing the sulfurcontained in these gasesby constituting a wall which is not easily fusible and consists of slagrich inlime of a spongy porous structure. For this purpose it is notsufficient to prepare a mass by mixing lime-milk and a fuel rich inashes. A mass of this description would I crack at the first action ofheat and then contin uously disintegrate. On the contrary, it isrequired that the mass consisting of lime and i a fuel rich in ashes bemixed with easilyburning fuel and with less easily-burning fueldistributed as uniformly as possible, the first serving by burning outrapidly to produce the porosity required for the dilatation of the massunder the influence of the increasing temperature, the latter forsecuring by burning out more slowly the porosity during thescorification and in the slag itself. In this manner a layer of slag ofsponge-like porosity is obtained.

I have found that the problem may be solved in practice by mixing asuniformly as possible lime-milk containing the required proportion oflime with sawdust,representing the easily-combustible component,not-caking fuel, representing the less-combustible component, and browncoal or peat, representing the component which furnishes principallyashes. Moreover, some caking fuel is advantageously added in order toimpart a certain degree of toughness to the mass.

Experiments carried on on a large scale and for a period of considerableduration have proved that the following combination is a very suitableone, viz: from ten to fifteen parts, by weight, of sawdust, from thirtyto thirty-five parts, by Weight, of not-caking fuel, (coke, anthracite,coal,) from twenty to twenty-five parts, by weight, of caking fuel, fromthirty to thirty-five parts, by weight, of peat. These substances aremixed with six to twenty parts, by weight, of caustic lime, as may berequired, tempered with a quantity of water equal to the weights of thecombustible material taken together. The mass, mixed as intimately anduniformly as possible, is

molded in the shape of plates, bricks, &c., and exposed to the air,whereby the caustic lime is converted into carbonate of lin1e,whichcements the parts of fuel together.

The plates, bricks, &c., are disposed either in layers alternating withthe fuel or they are arranged behind the fuel.

By the action of the fire the mass is converted into a sponge-likeporous slag wall, which in consequence of its considerable tenor in limecombines absolutely with the sulfur of the furnace-gases passing throughthe same and on-the other side enforces an intimate mixture of thefurnace-gases with the accompanying unconsumed air, whereby solid partsof coal, carbonic oxid, and products of smouldering and of distillationcontained in those gases are caused to be consumed. The result is thatthe chimney-stacks discharge into the atmospheric air the furnace-gasesessentially free of sulfurous acid, carbonic oxid, and soot,

I claim as my invention 1. A method for desulfurizing furnacegases,which consists in passing the gases through a filter arranged adjacentto the fuelplates of the furnace and formed by the action of the gasesupon a mass consisting of lime, sawdust, not-caking f-uel, caking fueland peat.

2. A method for desulfurizing furnacegases which cousistsin passing thegases through a mass consisting of caustic lime, an easily-combustiblecomponent, a less-combine tible component, and peat.

3. A method for desulfurizing furnacegases which consists in passing thegases through a sponge-like material formed by the action of the gasesupon a mass consisting of ten to fifteen parts by Weight of sawdust,thirty to thirty-five ,parts by Weight of not- EMIL POLLAOSEK.

Witnesses:

FRANK DYER CHESTER, T. LOGNOIDIO.

